Microseismic monitoring is frequently used to monitor hydraulic fracturing operations in order to provide information about the fracturing of the rocks to scientists and engineers. Such information can be used to control ongoing hydraulic fracturing, to help the scientists and engineers understand the likely resources available after the fracturing, to help design future hydraulic fracturing jobs, and so forth. This type of information can be derived from seismic measurements made on the surface and/or buried below the surface—including for example measurements of the motion of the ground responsive to the hydraulic fracturing. The seismic data, however, needs to be analyzed and processed before it can be useful in understanding the reservoir and the fracturing job. For example, the seismic data may need to be parsed to identify individual seismic events, to locate those events, to develop or refine a velocity model, to create an image of the subsurface, and so forth.